1. Field of the Invention
The present invention relates to the field of communication; and more particularly, a method for transferring data.
2. Description of Related Art
FIG. 1 illustrates a logical block diagram of a conventional communication system that provides mobility. This logical block diagram represents either wireless or wireline (or landline) communication systems that provide subscriber mobility. As shown, an end user 2 communicates with a destination entity 6 via a first communication device 4, a-serving system 12, a network 14, a home system 16, and a second communication device 8. The end user 2 represents an entity (human, system or machine) which generates information for communication to the destination entity 6 (also a human, system or machine).
The first communication device 4 represents a device for interfacing with the serving system 12. For instance, taking wireless communication as an example, the serving system 12 includes any number of base stations, mobile switching centers, authentication centers, etc. to provide wireless communication services for a coverage area in which the communication device 4 is located, and the communication device 4 represents a mobile station. Continuing with the wireless communication example, the network 14 presents a public or private communication network such as the Public Switch Telephone Network, a public packet network or a private packet network, and the home system 16 represents the wireless communication service provider with whom the user of the mobile station (i.e., the communication device 4) has established an agreement to provide mobile wireless communication services. Accordingly, the home system 16, like the serving system 12, also includes any number of base stations, mobile switching centers, authentication centers, etc. to provide mobile wireless communication services for a coverage area. Because a particular mobile wireless communication service provider has a limited coverage area, service providers having different coverage areas establish roaming agreements to serve each other's customers. In this example, the second communication device 8 could be a mobile station or wireline connection to the home system 16. Alternatively, in this example or any other embodiment, the second communication device 8 is connected to the home system 16 via a network such as the network 14. As a further alternative, the second communication device 8 forms part of the home system 16.
As an example of how FIG. 1 represents a wireline mobile communication system, the serving system 12 represents the landline mobile communication service provider for the location in which the communication device 4 is located, the network 14 represents, for example, a long distance landline carrier, and the home system 16 represents another landline mobile communication service provider with whom the end user 2 has established an agreement to provide landline mobile communication services. The first communication device 4 could then represent an intelligent or programmable phone. One embodiment of an intelligent phone allows the end user 2 to place a programmed integrated circuit card into the intelligent phone, and convert the intelligent phone into the end user's personal phone. Namely, the programmed integrated circuit card provides the intelligent phone with the subscriber information for the end user 2 such that communication of this information to the serving system 12 and communication between the serving system 12 and the home system 16 allows, for example, (1) calls to the end user 2 to be routed to the intelligent phone (i.e., communication device 4) or (2) the end user 2 to originate calls in the serving system 12 as if he were still in the area served by the home system 16.
The wireline and wireless examples given above provide only two examples of the many possible mobile communication systems represented by FIG. 1.
The mobile communication systems represented by the logical block diagram of FIG. 1 present various challenges to the serving system 12 and the home system 16 which want to provide communication services only to valid users and receive appropriate payment for having provided those services. Accordingly, each communication system has associated therewith numerous different standards and protocols for ensuring that the above mentioned goals are achieved.
The most prevalent techniques employed by these standards utilize permanent identifiers associated with the end user 2. One of the identifiers is assigned by the home system 16, and is referred to hereinafter as the first permanent identifier. The first permanent identifier includes two portions. The first portion includes routing information to the home system 16, and identifies the home system 16 with which the serving system 12 should communicate. The second portion of the first permanent identifier identifies the end user 2 to the home system 16, and is often an identification number. Many wireless communication standards refer to the first permanent identifier as the mobile station identifier (MSID).
An example of the first permanent identifier is the International Mobile Station (or Subscriber) Identification (IMSI) specified by the International Telecommunication Union—Telecommunication Sector (ITU-T) Recommendation E.212. The format of the IMSI is given below:IMSI (up to 15 digits)=MCC (3 digits)+MNC (1 to 3 digits)+MSIN (9-11 digits)The mobile country code (MCC) forms the first three digits of the IMSI and identifies the country in which the home system 16 is located. Together with the mobile network code (MNC), which forms the next 1 to 3 digits, the MCC forms a home system code identifying the home system 16. Communication standards in the United States often refer to this home system code as the home network identifier (HNI). The next 9-11 digits form the identification number pre-assigned to the end user 2 by the home system 16.
Another permanent user identifier (hereinafter “the second permanent identifier”), while known by the home system 16 and associated with the end user 2, is not necessarily assigned by the home system 16. This identifier is also associated in some manner with the first communication device 4 or a portion thereof being used by the end user 2. In a mobile wireless communication system, the second permanent identifier could be the electronic serial number (ESN) of the mobile station serving as the first communication device 4. In a wireline mobile communication system such as the intelligent phone example discussed above, the second permanent identifier could be the serial number of the programmed integrated circuit card. The second permanent identifier could even be the phone number of, for example, and integrated services digital network (ISDN) phone.
There are plans to expand the second permanent identifier in the future. The expanded second permanent identifier includes three portions. The first and second portions generally represent the unexpanded second permanent identifier, while the third portion represents the expanded portion of the second permanent identifier. The first portion includes a code. When that code is a pre-established code, the expanded second permanent identifier is triggered. Accordingly, this technique permits use of either unexpanded or expanded second permanent identifiers. If the expanded second permanent identifier is triggered, the system or device receiving the first and second portions of the expanded second permanent identifier will expect the third portion to follow, and if the third portion is not received, a request therefor will be generated.
When the first portion of the second permanent identifier does not include the pre-established code, the first portion represents a first identification number as in the unexpanded second permanent identifier. The second portion of the second permanent identifier, and also the expanded second permanent identifier, includes a second identification number. The expanded portion represents a third identification number.
An example of an expanded second permanent identifier is the expanded ESN (EESN) currently being proposed for wireless communication. The format of the EESN is given below:EESN (56 bits)=ESN (32 bits)+ESN-expansion (24 bits)ESN (32 bits)=manufacturer's code of 128 (8 bits)+identification number (24 bits)ESN-expansion=expanded manufacture's code (24 bits)When the manufacturer's code is 128, the expanded ESN is triggered.
The home system 16 typically stores the first and expanded second permanent identifier pair for each subscriber such as the end user 2. When communicating with the serving system 12, the communication device 4 supplies the first and expanded second permanent identifiers to the serving system 12. Based on the routing information in the first permanent identifier, the serving system 12 knows to communicate with the home system 16 to, for example, validate the end user 2. To validate the end user 2, the serving system 12 provides one or both of the first and expanded second permanent identifiers to the home system 16. Typically, if the home system 16 receives only one of these identifiers, the home system 16 will request the other identifier from the serving system 12. Furthermore, if an expanded second permanent identifier is supplied without the third or expanded portion, the home system 16 will request the expanded portion.
If both the first and expanded second permanent identifiers provided by the serving system 12 match a corresponding first and expanded second permanent identifier pair stored at the home station 16, the home station 16 validates the end user 2. This process may be used as part of a procedure to verify (for billing purposes) or authenticate (to eliminate fraud) the end user 2 as well. Referring again to the wireless example, this validation process is typically performed as part of the registration procedure included in most wireless communication standards.
Once validated, the serving system 12 provides communication services to the end user 2. For example, in a wireless system, a serving system 12 will open a traffic channel to a valid mobile station upon receiving such a request from the mobile station by the end user 2 originating the call. Having opened this traffic channel, the end user 2 can now transmit data to the destination entity 6.
A need, however, exists for end users to more efficiently transmit data than available through the lengthy process of requesting and establishing a traffic channel.